Radical Grammarian was at a party once where an acquaintance asked what proved to be a wildly unpopular question: why, she wondered, do we spend so much money, time, and energy trying to save the giant panda? Giant pandas are surely one of the most fragile and maladapted species ever to precariously cling to a vanishing habitat. They have only a single food source (bamboo), and the females have just a two- or three-day period of fertility each year–a great inconvenience, given the males’ notorious reluctance to mate. Clearly, this is a species that has gone up an evolutionary blind alley. “They’re crying out for extinction,” my acquaintance said, “just let them go!” All true, of course, but the answer to her original question is nevertheless pretty obvious: however maladapted giant pandas are for life in the twenty-first century, they are also unutterably cute and cuddly.
The bamboo forests of the English language have similar rare and fragile creatures. Some of them, like whence or whither, once roamed the plains in great numbers, turning up in the speech and writing of the great and humble alike. But now they are employed only in obviously formal or jocular contexts. Removed from that environment, they show no signs of breeding in captivity. Radical Grammarian finds whence and whither just as adorable as giant pandas, and would be sorry to see them go. But unlike the pandas, these little curiosities thrive in their role as deliberate archaisms, and their natural habitat of jocular or formal contexts isn’t going anywhere. It’s for that reason that nobody much bothers with trying to preserve them: they really don’t need the help.
So why, then, do some people go to such great lengths to try to preserve whom? Radical Grammarian has nothing in particular against this word, and in fact, he is not above employing an occasional whom, if, say, he wants to sound as if he might know the function of all the forks at a formal dinner party. But the fact is that for virtually all speakers, the hardier who has driven its meeker cousin out of most of the grammatical contexts in which it once lived. Every speaker of English alive today knows a couple of things about this word: first, that it is a semi-archaic form sometimes used in place of who in formal speech or writing, and second, that mastering its use requires something beyond the natural process of acquiring the language natively.
The who/whom distinction is ostensibly parallel to the he/him distinction, i.e. a simple alternation between nominative and accusative (or, if you prefer, “subjective” and “objective”) case. Yet everybody naturally knows how the latter works, while the former must be consciously learned. Popular grammar guides even rely on this fact: they recommend substituting he or him (on the correct assumption that everybody knows how to do this) as a test to decide if who or whom is appropriate in a given sentence.
Employing the he/him test would have you using whom every time in the context of the object of a verb or preposition. But “object of a verb or preposition” is a very, very, very common environment. Trying to force whom into these contexts is like trying to force the giant panda to live on the streets of New York or the sands of the Kalahariâ€“this is simply is not its natural environment. And that’s why so much ink has to be spilled about it in grammar guides: even highly educated people feel some confusion about whom, resulting in well-worn solecisms like “whom shall I say is calling?”
The irony here is that all the fuss is for nothing: whom isn’t really in mortal danger, because there is one place where whom is the only acceptable form, for pretty much all speakers. That place is in the object position of a “fronted” preposition, such as in “the cast member of Friends to whom they sent a mash note”. It’s universally regarded as incorrect to say “*the cast member of Friends to who they sent a mash note,” though of course one can use the more colloquial “who they sent a mash note to.” This, then, is whom‘s natural habitat, where even those to whom the word is only a casual acquaintance agree that it’s the only choice.
For those who insist on continuing to use whom according to the traditional rule, here is what Radical Grammarian would say to you: Bully for you! You have successfully mastered a mildly difficult point of archaic grammar. Please feel free to continue to employ this hard-won skill in formal writing and even in polite conversation. Radical Grammarian will not advocate that anyone openly mock and deride you (civility being an all too rare commodity in discourse on matters grammatical), though he won’t object too loudly if someone does. But please spare the rest of us from any extraordinary measures to prolong the survival of this fragile giant pronoun. It’s just not that cute.